This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Development of metal ion affinity chromatography (IMAC) methodology for the isolation of phospho-peptides at the sub-picomole level. Applications to determination of sites of phosphorylation on a variety of biologically important proteins. (Additional effort and instrument time reported under Collaborative projects and other Technical Research and Development project.)